Abstract:To investigate the effects of heat treatment processes, and the dose-dependent effects of sucrose addition during preparation on the gel properties of the resulting soybean powders, this study compared the dispersibility and solubility of soybean powder produced under different heat treatment processes with various amounts of sucrose addition. Changes in GDL-induced gel rheological properties, gel strength, microstructure, water holding capacity, water distribution, and gel intermolecular force were also analyzed. Heat treatments during production, including baking, boiling, concentration, and spray drying, reduce the dispersion of soybean powder, thereby reducing the water holding capacity, storage modulus (G') and gel strength of the GDL-induced gel. Additionally, the gel microstructure changes from a dense and uniform state to a loose, large-pore structure. Comparison with the control group reveals that spray drying increases the dispersion time of soybean powder from 59.67 s to 550.50 s, and extends the T22 relaxation time of the gel from 113.02 ms to 194.85 ms. Addition of 20% sucrose shortened the dispersion time of soybean powder to 52.50 s, and reduced the T22 relaxation time of the gel to 110.74 ms, effectively improving the GDL-induced gel properties. The intermolecular forces in the gels formed by soybean powder produced under different heat treatment processes and sucrose addition levels are primarily hydrophobic and electrostatic interactions. In summary, spray drying and sucrose addition at mass fractions less than 5% are key factors underlying poor dispersibility and gelation of soybean powder products. This study provides a theoretical basis for the preparation of soybean powder products with good dispersibility and gelation properties.
